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path: root/drivers/char/watchdog/sa1100_wdt.c
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Diffstat (limited to 'drivers/char/watchdog/sa1100_wdt.c')
-rw-r--r--drivers/char/watchdog/sa1100_wdt.c49
1 files changed, 10 insertions, 39 deletions
diff --git a/drivers/char/watchdog/sa1100_wdt.c b/drivers/char/watchdog/sa1100_wdt.c
index 1b2132617dc..fb88b4041dc 100644
--- a/drivers/char/watchdog/sa1100_wdt.c
+++ b/drivers/char/watchdog/sa1100_wdt.c
@@ -36,13 +36,10 @@
#include <asm/uaccess.h>
#define OSCR_FREQ CLOCK_TICK_RATE
-#define SA1100_CLOSE_MAGIC (0x5afc4453)
static unsigned long sa1100wdt_users;
-static int expect_close;
static int pre_margin;
static int boot_status;
-static int nowayout = WATCHDOG_NOWAYOUT;
/*
* Allow only one person to hold it open
@@ -62,55 +59,33 @@ static int sa1100dog_open(struct inode *inode, struct file *file)
}
/*
- * Shut off the timer.
- * Lock it in if it's a module and we defined ...NOWAYOUT
- * Oddly, the watchdog can only be enabled, but we can turn off
- * the interrupt, which appears to prevent the watchdog timing out.
+ * The watchdog cannot be disabled.
+ *
+ * Previous comments suggested that turning off the interrupt by
+ * clearing OIER[E3] would prevent the watchdog timing out but this
+ * does not appear to be true (at least on the PXA255).
*/
static int sa1100dog_release(struct inode *inode, struct file *file)
{
- OSMR3 = OSCR + pre_margin;
-
- if (expect_close == SA1100_CLOSE_MAGIC) {
- OIER &= ~OIER_E3;
- } else {
- printk(KERN_CRIT "WATCHDOG: WDT device closed unexpectedly. WDT will not stop!\n");
- }
+ printk(KERN_CRIT "WATCHDOG: Device closed - timer will not stop\n");
clear_bit(1, &sa1100wdt_users);
- expect_close = 0;
return 0;
}
static ssize_t sa1100dog_write(struct file *file, const char *data, size_t len, loff_t *ppos)
{
- if (len) {
- if (!nowayout) {
- size_t i;
-
- expect_close = 0;
-
- for (i = 0; i != len; i++) {
- char c;
-
- if (get_user(c, data + i))
- return -EFAULT;
- if (c == 'V')
- expect_close = SA1100_CLOSE_MAGIC;
- }
- }
+ if (len)
/* Refresh OSMR3 timer. */
OSMR3 = OSCR + pre_margin;
- }
return len;
}
static struct watchdog_info ident = {
- .options = WDIOF_CARDRESET | WDIOF_MAGICCLOSE |
- WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
- .identity = "SA1100 Watchdog",
+ .options = WDIOF_CARDRESET | WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
+ .identity = "SA1100/PXA255 Watchdog",
};
static int sa1100dog_ioctl(struct inode *inode, struct file *file,
@@ -172,7 +147,7 @@ static struct file_operations sa1100dog_fops =
static struct miscdevice sa1100dog_miscdev =
{
.minor = WATCHDOG_MINOR,
- .name = "SA1100/PXA2xx watchdog",
+ .name = "watchdog",
.fops = &sa1100dog_fops,
};
@@ -194,7 +169,6 @@ static int __init sa1100dog_init(void)
if (ret == 0)
printk("SA1100/PXA2xx Watchdog Timer: timer margin %d sec\n",
margin);
-
return ret;
}
@@ -212,8 +186,5 @@ MODULE_DESCRIPTION("SA1100/PXA2xx Watchdog");
module_param(margin, int, 0);
MODULE_PARM_DESC(margin, "Watchdog margin in seconds (default 60s)");
-module_param(nowayout, int, 0);
-MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started");
-
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);